Sasha CampbellThose tiny, immobile pests that appear like small bumps on your plants are likely scale insects.
They feed by sucking sap from plants, causing them to wilt and appear sickly. Additionally, the leaves may turn yellow and drop off.
Scale insects are of the order Hemiptera [1]. They can cause serious damage to the garden, greenhouse, and houseplants, depending on the extent of the infestation. As a result, you must get rid of them.
Scale bugs are identified by tiny, shell-like bumps clustered along plant stems. They excrete a sticky honeydew substance, which often attracts fungi and sooty mold on plants.
How to Get Rid of Scale on Plants Naturally
Below are some common home remedies and natural solutions that you can try.
1. Rub Them Off
If the problem is small, this is the most inexpensive way to control the critters. Therefore, this method is beneficial for controlling houseplant scale insects.
An old toothbrush is a good tool for scraping or rubbing the pests off the stems. Alternatively, a slightly abrasive sponge or cotton swab dabbed in rubbing alcohol should do the trick.
Also, check under leaves where they may be hiding. Afterward, you can spray with an organic insecticide to prevent reinfestation.
2. Horticultural Oil
Purchase horticultural oil at the garden store or online. It is also known as summer oil or dormant oil. Spray all infected plants with the product as per the manufacturer’s instructions.
The oil smothers the critters. However, repeated applications may be necessary to eliminate an infestation. Choose a dry day with low humidity and no high winds to apply it to the infected plants.
Alternatively, a DIY horticultural oil solution might be less expensive. Combine one tablespoon of organic liquid soap with a cup of vegetable oil for the recipe.
Next, add one tablespoon of this mixture to a cup of water. Finally, shake well and coat the affected plants with your homemade scale spray.
Use the measurement as a guide for larger portions.
3. Pruning
Pruning is a great practice to remove tree scale insects, as an infestation may require drastic action.
If you act fast, this home remedy will stop pests at an early stage, preventing them from spreading to other areas. Additionally, there will be no honeydew to attract other pests.
Afterward, burn or remove pruned plant parts from the garden. Pruning may also strengthen plants and help them resist further damage.
4. Beneficial Insects
Using beneficial insects is one of the main biological methods for controlling pest infestations. Predatory insects, such as parasitic wasps and lacewings, prey on small insects, including plant scales.
Plus, you can purchase most of these beneficial insects at various garden centers or online.
It is also possible to encourage them to visit your garden. Plant flowers like yarrow and cosmos to attract them.
5. Neem Oil
Neem comes from the seeds of the neem tree. Farmers have been using it for many years as a natural pesticide.
Mix 2 teaspoons of liquid soap with 2 tablespoons of neem oil and 1 gallon of warm water to use neem oil for scale insects. Finally, shake well and spray the infested plants.
You can also find this natural treatment as a concentrate. It comes mixed with other active ingredients in organic commercial sprays.
Neem oil will block the breathing holes of these pests, suffocating them to death.
6. Insecticidal Soap
Insecticidal soap is another excellent home remedy for treating plant scales naturally. So, let’s make a homemade insecticidal soap spray to kill scales.
Dawn dish soap, or any household liquid soap mixed with water and vegetable oil, can do the trick. However, we prefer using organic soaps.
Combine 5 tablespoons of liquid soap with 2 tablespoons of vegetable oil, then add 1 gallon of warm water. Shake well.
Finally, spray the DIY scale-infestation spray on the affected plants.
You can also purchase commercially available insecticidal soap.
7. Bug Blaster
This scale insect control method relies on a powerful blast of water to remove the critters.
The apparatus consists of a ‘wand’ and a nozzle. It is specially designed to kill soft-bodied pests without harming your plants.
Bug Blaster is also economical with water, and any excess on plants will be usefully absorbed. However, if the pests return, repeat the process.
You can also use this tool to keep your plants clean.
8. Azadirachtin
Azadirachtin is one of the best insecticides for scale insects on plants. It is widely used as an organic pesticide to naturally control a range of other soft-bodied insects.
It disrupts the insects’ normal life cycle. The pests will eventually die.
Additionally, if you use the product as directed by the manufacturer, it will not harm most beneficial insects, pets, or humans.
9. Essentria IC-3
This commercial product controls many pests.
Essentria IC-3 contains a blend of essential oils and other ingredients. It is a multipurpose natural insecticide containing rosemary oil, peppermint oil, and geraniol.
This plant-scale treatment can be used for spraying or misting, as directed by the manufacturer. It can also be used to drench surfaces and paths to eliminate or prevent pest infestations.
Essentria IC-3 is effective against white scales on plants. Additionally, with caution, you can use it directly on cattle, horses, and chickens.
It also works against many other crawling and flying insect pests.
10. Diatomaceous Earth (DE)
This white powder is composed of the crushed skeletons of microscopic marine creatures.
Diatomaceous earth is mildly abrasive, which helps kill scale pests. It also works on many other harmful insects.
The sharpness of diatomaceous earth cuts into insect pests, causing dehydration and death.
Moreover, DE is readily available. Purchase it online or from your local garden store. As a preventive measure, dust it on plant surfaces and around the base.
Takeaway
Scale damage to plants may be unsightly. The pests may also affect houseplants, garden flowers, shrubs, fruit trees, and vegetable crops.
Try the natural remedies above to eliminate them and keep your plants pest-free.
I have hard scale insects on my water lilies in the koi pond. They are on the lily pads and stems. How did this happen and how to get rid of them?